Compact relay with angular pole pieces



June 23, 1964 A Q ADAMS 3,138,677

COMPACT RELAY WITH ANGULAR POLE PIECES Filed May 29, 1961 2 Sheets-Sheet 1 FIG.|

INVEN TOR.

ANDREW O. ADAMS ATTORNEY June 23, 1964 A. o. ADAMS COMPACT RELAY WITH ANGULAR POLE PIECES 2 Sheets-Sheet 2 Filed May 29, 1961 FIG 4 lOb INVENTOR.

ANDREW O ADAMS FIG. 5

ATTORNEY United States Patent 3,138,677 COMPACT RELAY WITH AN GULAR POLE PIECES Andrew 0. Adams, Inglewood, Califl, assignor to Leach Corporation, San Marino, Califi, a corporation of California Filed May 29, 1961,, Ser. No. 113,366 7 Claims. (Cl. 200-87) This invention pertains to a relay of compact construction and reliable operation.

The relay of this invention includes an actuating coil from which pole pieces extend transversely and are bent inwardly along one side of the coil extending at an acute angle to the axis of the coil. An armature is pivotal about an axis perpendicular to that of the coil and located at the side of the coil so that the armature can contact pole faces on the angular extensions of the pole pieces. The ends of the pole piece extension approach each other and are located close to .the pivot axis of the armature, thereby reducing the average working gap for the armature. A relatively strong return spring engages the armature adjacent the pivotal axis, biasing it to the open position. As a result of this construction, the relay is made compact in size, the armature is balanced and there is a particularly large force for pivoting the armature upon energization of the coil.

The use of a strong return spring engaging the armature near its pivotal axis results in a substantially constant spring force regardless of the position of the armature. It also retains the armature firmly in its bearing support to avoid chatter. Conventional practice has been to engage the end portion of the armature by a relatively Weak spring. This type of spring, by having a relatively high mechanical advantage, can effectively bias the armature to its open position. However, the spring force increases substantially as the armature rotates, and the weak spring does not serve to retain the armature pivot firmly within its bearing.

Therefore, it is an object of this invention to provide a compact relay of reliable construction.

Another object of this invention is to provide a relay in which a substantially constant return force is exerted on the armature.

A further object of this invention is to provide a relay of balanced construction such that vibration will not cause undesired pivotal movement of the armature.

An additional object of this invention is to provide a relay in which a strong magnetic force is exerted on the armature when the coil is energized.

These and other objects will become apparent from the following detailed description taken in connection with the accompanying drawing in which:

FIG. 1 is a top plan view of the relay of this invention,

FIG. 2 is a side elevational view of the delay,

FIG. 3 is an end elevational view thereof taken on the right hand side of FIG. 1 and FIG. 2,

FIG. 4 is a transverse sectional view taken along line 44 of FIG. 2 illustrating the switch blade and contact construction, and

FIG. 5 is a fragmentary plan view showing the armature in its alternate position.

With reference to the drawing, the relay of this invention includes an electromagnetic coil 1 through which a core 2 passes. The ends of the core engage pole pieces 3 and 4 which extend transversely in the same direction to one side of the coil, and are formed with angular extensions 5 and 6. The latter portions extend along the side of the coil toward its midpoint. The extensions 5 and 6 are positioned at an acute angle to the axis of the coil 1, and include parallel inner faces 7 and 8.

The coil and pole pieces are supported by wire brackets 9 and 10. These elements are of left and right hand configuration, but otherwise are identical. As best seen in FIG. 3 bracket 10 includes parallel top and bottom sections 10a and 10b that are welded to the lower edge of pole piece 4 and the top of header 13, respectively. These portions of the support are interconnected by upstanding segment 10c, while a similar portion 10d depends from the end of top segment 10a. An extension 10e projects from leg 10d and is welded to the header 13 lengthwise of the coil. This provides support units of box-like construction, secured both transversely and longitudinally of the unit. The result is a particularly rigid yet light weight and simple support, resistant to vibrational forces.

An armature 14 of magnetic material is positioned bebetween the pole piece extensions 5 and 6 along the side of the coil 1. The armature includes centrally located journals 15 and 16 that are received within openings formed in support plates 17 and 18, thereby positioning the armature for rotation about an axis perpendicular to that of the coil and located substantially at the midpoint of the length of the coil. This axis is parallel to faces 7 and 8 of the pole piece extensions 5 and 6, and the ends 19 and 20 of these pole extensions are positioned relatively close to the pivot axis. Washers 22 and 23 interposed between the armature and the supports 17 and 18 assure the free pivotal movement of the armature.

The support members 17 and 18 are of course nonmagnetic and are carried by the extensions 5 and 6 of the pole pieces by being welded thereto on their upper and lower edge surfaces. In assembling the armature support, the coil 1 is energized before members 17 and 18 are welded in place. This permits the armature to be positioned and held in exactly the proper relationship with respect to the pole faces when the supports 17 and 18 are secured. As a result, the armature is given a precision setting without extensive adjustment. Equal gaps 24 and 25 are formed between faces 7 and 8 of the pole pieces and surfaces 26 and 27 of the armature when the latter member is open as in FIG. 1.

A stop member 28 is secured to pole piece 4 extending angularly therefrom along the side of the coil where it is spaced from surface 8 of the pole piece extension 6. The end 29 of the armature is engagable with the stop, which thereby limits movement of the armature in a clockwise direction as seen in FIG. 1.

The armature is biased by means of a return spring 30 to the open position of FIG. 1 where it engages the stop. This is a leaf spring element, suitably secured to pole piece 3 and extending therefrom to a rounded distal end 31 that bears against the vertical surface of the armature 14 adjacent the journals 15 and 16 on the side opposite end 29. Spring 30 is a relatively stiff spring so that despite the fact that the spring end 31 is positioned very close to the pivotal axis of the armature, it exerts an adequate biasing force on the armature to preclude movement of the armature from vibrational, gravitational or other forces imposed upon it. This strong spring also holds the journals firmly against the sides of the openings receiving the journals in the support members 17 and 18. This assures that the journals will not chatter within the openings in the support members. The use of the strong spring 30, as contrasted with a light wire spring as in conventional designs, also means that the spring torque on the armature is substantially the same for all rotational positions of the armature. In prior art arrangements where a light spring contacts the end portion of the armature so as to achieve an adequate rotative force through the high mechanical advantage, there is an undesirable buildup of force during the movement of the armature. Such increase in force is obviated by the design of this invention.

Located at the opposite ends of armature 14 are actuators 32 and'33. These are'wire elements which may be welded to the end surfaces of the armature, extending downwardly therefrom and terminating in ends 34 and 35 f insulating material-such as glass. These ends of the actuators, as bestseen in FIG. 4, are disposed adjacent -tlie distalends of contactblades 36 and 37. The opposite ends-of the blades-36 and 37 are carried by pins 38 and 39*that project frorn header 13. These resilient'blade ele- 'ments are biased against stationary contacts 40 and 41 carried by pins 42 and 43. The contacts 40 and 41 are spaced from opposed-stationary contacts 44 and 45. The latter elements are supported by pins 46'and 47, likewisecarriedby the header 13.

It-canbe seen, therefore, that with the relay in its deenergized position, as illustrated, the ends 34 and 35 of the actuators are spaced from the corresponding ends of the resilient switch blades 36 and 37, which thereby assume their normal-position in engagement-with contacts 40 and 41. Upon energization of coil 1, flux flows through core 2-, pole pieces 3 and 4, and acrossthe gaps 2'4 and 25. This causes the armature to rotate counterclockwise so that it is brought into engagement with the surfaces 7 and 8 of the pole piece extensions as seen in FIG. 5. This moves the actuators 32 and 33, causing them to engage the ends of contact blades 36 and 37 so as to open contacts 40 and 41, and close contacts 44 and 45. When thecoil is deenergized, the return spring brings 'the armature back to the position of FIG. 1, and the blades 36 and 37 return to their usual position against contacts 40 and 41.

As a result of the-construction of this relay, a unit of particularly compact size can be achieved. This results respect to the axis of the coil permits the overall width ofthe armature and pole assembly tobe reduced substantially. The armature is pivoted about its midpoint so that it is balanced andwill not rotate prematurely from external'loads applied to it.

Locating the ends 19 and 20 of the pole piece extensions and 6 adjacent the axis of rotation of the armature results in a large projected area at the working gaps to reduce the reluctance in the magnetic circuit. It also serves to materially reduce the working gap of the armature. When the relay is'in the open position of FIG. 1 it may be seen that ends 19 and 20 of the pole pieces are at the minimum distance to the corresponding armature faces 26 and 27. This is due to'a slight angularity between the armatureand the pole extensions resulting in an outward divergence along the adjacent faces 7 and 26, and 8 and 27. Nevertheless, when the armature is closed as seen in FIG. 5, the ends 19 and'2tl of the core extensions remain slightly spaced from the surface of the armature. Despite the small gap at-the ends of the pole extensions prior to movement of the armature, therefore, adequate rotational movement'of the armature is permitted. The result is a working gap of reduced dimension, and in view of'the fact that the actuating force is inversely proportional to the square of the width of the gap, a significantly greater torque is realized.

Furthermore, while there is a slight angularity between the faces of the armature andthe pole pieces, these surfaces are more nearly parallel'than in conventional designs. This gives a desirable straight line flux path across the gaps which also increases the available torque on the armature.

The foregoing detailed description is to be clearly understood as given by way of illustration and'example only, the. spiritand scope of this invention being limited solely bythe appended claims.

I claim: 7 l. A relay comprising a coil, a core extending through said coil, a duality of pole pieces, said pole pieces being disposed one at either end of said coil and engaging said core, said pole pieces extending laterally from said core to one side of said coil, and including extensions on said one side extending inwardly toward the midportion of said coil, said pole extensions having surfaces falling in substantially parallel planes which planes are at an acute angle with respect to the axis of said coil, an armature, means pivotally mounting said armature about an axis at said one side of said coil between said pole extensions, said axis being substantially at right angles to the axis of said coil, said armature being pivotal between a position of engagement with said pole extensions and a position remote therefrom, and a leaf spring, said spring being relatively stiff and having an outer end bearing against said armature at a point on one side of and in juxtaposition with said axis of said armature for biasing said armature to said position remote from said pole extensions, said spring being remote. fromsaid armature at locations other than at said outer end of said spring.

2.. A relay comprising a coil, a core extending through said coil, aduality'of pole pieces located one at either end of said coil'in engagement with said core, each of said pole pieces extending laterally to oneside of said coil and including an extension projecting toward the mid portion of said coil on said side, said extensions terminating in adjacent relatively closely spaced ends, said extensions having opposed faces falling in substantially parallel planes which intersect the axis of said coil at an acute angle, an armature, and means pivotally mounting said armature about an axis on said one'side of saidcoil substantially at right angles to said axis of said coiland lo- .cated intermediate the ends of said extensions and in juxtaposition therewith, whereby said armature is pivotal between a position in which opposite faces thereof on opposite sides of said pivotal axis thereof engage said opposed faces of said extensions, and a position in which said' opposite faces are remote'from said opposed faces, said armature being mounted to provide a minimum space between said opposite faces and said opposed faces at the endsof saidextensions when insaid remote position, and to contact said opposed faces only inwardly of 'said'ends thereof when in said' position of engagement,

each of said opposite faces diverging from the adjacent one of said opposed faces from the location of said contact therewith to the end of said adjacent face wlie'nsaid armature is in said position of engagement.

3. A device as recited in claim 2 including in addition a stop limiting the travel of said armature to saidposition remote from said pole extensions, and a spring for biasing "said armature toward said remote position, said spring being relatively strong and engaging said armature at a point on one side of said pivotal axis and in juxtaposition therewith, .and being remote from said armature at locations other than at said point.

4. A relay comprising a .coil, a core extending through 'saidcoil, a duality of pole pieces located one at either end of said coil in engagement with said core, each of said pole pieces extending laterally to one side of said coil and including an extension projecting toward'the mid portion of said coil on said side, said extensions terminating in. adjacent relatively closely spaced ends, said extensions having opposed facesfalling in substantially parallel planes which intersect the axis ofsaid coil at an acute angle, an armature, and means pivotallymounting said armature about an axis on said one side ofsaid coil I substantially at right angles to'said axisof said coil and ends of said extensions when in said remote position, and to contact said opposed faces only inwardly of said ends thereof when in said position of engagement, said mounting means comprising a duality of support members carried by said extensions on opposite edges thereof, and journal means engaging said support members in the portions thereof between said ends of said extensions.

5. A relay comprising an electromagnetic coil, a core extending through said coil, a duality of pole pieces connected one on either end of said core, said pole pieces extending transversely in the same direction to one side of said coil, and having extensions projecting inwardly toward the midpoint of said coil, said pole pieces having opposed contact faces in spaced substantially parallel planes that intersect the axis of said coil at an acute angle, an armature, means symmetrically mounting said armature for pivotal movement about an axis intermediate the ends of said pole extensions and said planes of said contact faces, a duality of actuators carried by said armature one on either side of said pivotal axis, each of said actuators having a distal end, a duality of contact blades, a duality of spaced fixed contacts for each contact blade, each of said contact blades having a free end interposed between the fixed contacts therefor and biased against one of said fixed contacts, said armature being pivotal between a first position remote from said contact faces of said pole extensions and a second position of engagement therewith, the distal ends of said actuators being remote from said contact blades in said first position of said armature, and engageable with said free ends of said contact blades for moving said blades to a position of engagement with the others of said dualities of fixed contacts upon movement of said armature to said second position, and a leaf spring, said leaf spring having an outer end engaging said armature in juxtaposition with said axis for exerting a force on said armature biasing said armature toward said first position.

6. A device as recited in claim 5 in which the adjacent ends of said pole extensions are in juxtaposition with opposite faces of said armature at said pivotal axis thereof, the gaps between said armature and said contact faces when said armature is in said first position being at a minimum at said ends of said pole extensions, said ends of said pole extensions being spaced from said faces of said armature when said armature is in said second position.

7. A device as recited in claim 5 in which said means for mounting said armature includes a duality of support members in spaced parallelism, said support members being welded to the opposite edge surfaces of said pole extensions and extending between the adjacent ends of said pole extensions, said armature being journaled in said support members.

References Cited in the file of this patent UNITED STATES PATENTS 1,104,077 Smith July 21, 1914 1,283,507 Harding Nov. 5, 1918 1,302,817 Leonard May 6, 1919 1,859,934 Phelan May 24, 1932 1,886,372 Bossart Nov. 8, 1932 2,055,175 Franz Sept. 22, 1936 2,455,049 Edwards et al Nov. 30, 1948 2,760,026 Horlacher Aug. 21, 1956 2,810,037 Faus et al. Oct. 15, 1957 2,827,528 Girdwood et al. Mar. 8, 1958 2,902,565 Angold Sept. 1, 1959 2,965,954 Baker Dec. 27, 1960 3,030,469 Lazich Apr. 17, 1962 3,041,422 Greshel June 26, 1962 3,042,775 Jordan July 3, 1962 3,060,292 Moenke Oct. 23, 1962 

1. A RELAY COMPRISING A COIL, A CORE EXTENDING THROUGH SAID COIL, A DUALITY OF POLE PIECES, SAID POLE PIECES BEING DISPOSED ONE AT EITHER END OF SAID COIL AND ENGAGING SAID CORE, SAID POLE PIECES EXTENDING LATERALLY FROM SAID CORE TO ONE SIDE OF SAID COIL, AND INCLUDING EXTENSIONS ON SAID ONE SIDE EXTENDING INWARDLY TOWARD THE MIDPORTION OF SAID COIL, SAID POLE EXTENSIONS HAVING SURFACES FALLING IN SUBSTANTIALLY PARALLEL PLANES WHICH PLANES ARE AT AN ACUTE ANGLE WITH RESPECT TO THE AXIS OF SAID COIL, AN ARMATURE, MEANS PIVOTALLY MOUNTING SAID ARMATURE ABOUT AN AXIS AT SAID ONE SIDE OF SAID COIL BETWEEN SAID POLE EXTENSIONS, SAID AXIS BEING SUBSTANTIALLY AT RIGHT ANGLES TO THE AXIS OF SAID COIL, SAID ARMATURE BEING PIVOTAL BETWEEN A POSITION OF ENGAGEMENT WITH SAID POLE EXTENSIONS AND A POSITION REMOTE THEREFROM, AND A LEAF SPRING, SAID SPRING BE- 